Add initial version of the CfApi backend

For now this implements only the logic necessary to get a test suite
equivalent to the TestSyncVirtualFiles one to pass. It doesn't (yet)
honor request to fetch files from the system.

Signed-off-by: Kevin Ottens <kevin.ottens@nextcloud.com>

src/libsync/CMakeLists.txt

@@ -61,6 +61,12 @@ set(libsync_SRCS
     vfs/suffix/vfs_suffix.cpp
 )
 
+if (WIN32)
+    set (libsync_SRCS ${libsync_SRCS} vfs/cfapi/vfs_cfapi.cpp)
+    add_definitions(-D_WIN32_WINNT=_WIN32_WINNT_WIN10)
+    list(APPEND OS_SPECIFIC_LINK_LIBRARIES cldapi)
+endif()
+
 if(TOKEN_AUTH_ONLY)
     set (libsync_SRCS ${libsync_SRCS} creds/tokencredentials.cpp)
 else()

src/libsync/vfs/cfapi/vfs_cfapi.cpp

@@ -0,0 +1,529 @@
+/*
+ * Copyright (C) by Kevin Ottens <kevin.ottens@nextcloud.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#include "vfs_cfapi.h"
+
+#include <QDir>
+#include <QFile>
+
+#include "syncfileitem.h"
+#include "filesystem.h"
+#include "common/syncjournaldb.h"
+
+#include <cfapi.h>
+#include <comdef.h>
+
+Q_LOGGING_CATEGORY(lcCfApi, "nextcloud.sync.vfs.cfapi", QtInfoMsg)
+
+namespace {
+void CALLBACK cfApiFetchDataCallback(_In_ CONST CF_CALLBACK_INFO* callbackInfo, _In_ CONST CF_CALLBACK_PARAMETERS* callbackParameters)
+{
+    qCCritical(lcCfApi) << "Got in!";
+    Q_ASSERT(false);
+}
+
+CF_CALLBACK_REGISTRATION cfApiCallbacks[] = {
+    { CF_CALLBACK_TYPE_FETCH_DATA, cfApiFetchDataCallback },
+    CF_CALLBACK_REGISTRATION_END
+};
+
+std::unique_ptr<void, void(*)(HANDLE)> handleForPath(const QString &path)
+{
+    if (QFileInfo(path).isDir()) {
+        HANDLE handle = nullptr;
+        const qint64 openResult = CfOpenFileWithOplock(path.toStdWString().data(), CF_OPEN_FILE_FLAG_NONE, &handle);
+        if (openResult == S_OK) {
+            return {handle, CfCloseHandle};
+        }
+    } else {
+        const auto handle = CreateFile(path.toStdWString().data(), 0, 0, nullptr,
+                                       OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, nullptr);
+        if (handle != INVALID_HANDLE_VALUE) {
+            return {handle, [](HANDLE h) { CloseHandle(h); }};
+        }
+    }
+
+    return {nullptr, [](HANDLE){}};
+}
+
+DWORD sizeToDWORD(size_t size)
+{
+    return OCC::Utility::convertSizeToDWORD(size);
+}
+
+void deletePlaceholderInfo(CF_PLACEHOLDER_BASIC_INFO *info)
+{
+    auto byte = reinterpret_cast<char *>(info);
+    delete[] byte;
+}
+
+std::unique_ptr<CF_PLACEHOLDER_BASIC_INFO, decltype(&deletePlaceholderInfo)> findPlaceholderInfo(const QString &path)
+{
+    auto handle = handleForPath(path);
+    if (!handle) {
+        return {nullptr, deletePlaceholderInfo};
+    }
+
+    constexpr auto fileIdMaxLength = 128;
+    const auto infoSize = sizeof(CF_PLACEHOLDER_BASIC_INFO) + fileIdMaxLength;
+    std::unique_ptr<CF_PLACEHOLDER_BASIC_INFO, decltype(&deletePlaceholderInfo)> info(reinterpret_cast<CF_PLACEHOLDER_BASIC_INFO *>(new char[infoSize]), deletePlaceholderInfo);
+    const qint64 result = CfGetPlaceholderInfo(handle.get(), CF_PLACEHOLDER_INFO_BASIC, info.get(), sizeToDWORD(infoSize), nullptr);
+
+    if (result == S_OK) {
+        return info;
+    } else {
+        return {nullptr, deletePlaceholderInfo};
+    }
+}
+
+bool setPinState(const QString &path, CF_PIN_STATE state, CF_SET_PIN_FLAGS flags)
+{
+    if (!findPlaceholderInfo(path)) {
+        return false;
+    }
+
+    const auto handle = handleForPath(path);
+    if (!handle) {
+        return false;
+    }
+
+    const qint64 result = CfSetPinState(handle.get(), state, flags, nullptr);
+    if (result != S_OK) {
+        qCWarning(lcCfApi) << "Couldn't set pin state for" << path << ":" << _com_error(result).ErrorMessage();
+    }
+    return result == S_OK;
+}
+
+OCC::Result<void, QString> createPlaceholderInfo(const QString &path, time_t modtime, qint64 size, const QByteArray &fileId)
+{
+    const auto fileInfo = QFileInfo(path);
+    const auto localBasePath = QDir::toNativeSeparators(fileInfo.path()).toStdWString();
+    const auto relativePath = fileInfo.fileName().toStdWString();
+
+    const auto fileIdentity = QString::fromUtf8(fileId).toStdWString();
+
+    CF_PLACEHOLDER_CREATE_INFO cloudEntry;
+    cloudEntry.FileIdentity = fileIdentity.data();
+    const auto fileIdentitySize = (fileIdentity.length() + 1) * sizeof(wchar_t);
+    cloudEntry.FileIdentityLength = sizeToDWORD(fileIdentitySize);
+
+    cloudEntry.RelativeFileName = relativePath.data();
+    cloudEntry.Flags = CF_PLACEHOLDER_CREATE_FLAG_MARK_IN_SYNC;
+    cloudEntry.FsMetadata.FileSize.QuadPart = size;
+    cloudEntry.FsMetadata.BasicInfo.FileAttributes = FILE_ATTRIBUTE_NORMAL;
+    OCC::Utility::UnixTimeToLargeIntegerFiletime(modtime, &cloudEntry.FsMetadata.BasicInfo.CreationTime);
+    OCC::Utility::UnixTimeToLargeIntegerFiletime(modtime, &cloudEntry.FsMetadata.BasicInfo.LastWriteTime);
+    OCC::Utility::UnixTimeToLargeIntegerFiletime(modtime, &cloudEntry.FsMetadata.BasicInfo.LastAccessTime);
+    OCC::Utility::UnixTimeToLargeIntegerFiletime(modtime, &cloudEntry.FsMetadata.BasicInfo.ChangeTime);
+
+    if (fileInfo.isDir()) {
+        cloudEntry.Flags |= CF_PLACEHOLDER_CREATE_FLAG_DISABLE_ON_DEMAND_POPULATION;
+        cloudEntry.FsMetadata.BasicInfo.FileAttributes = FILE_ATTRIBUTE_DIRECTORY;
+        cloudEntry.FsMetadata.FileSize.QuadPart = 0;
+    }
+
+    const qint64 result = CfCreatePlaceholders(localBasePath.data(), &cloudEntry, 1, CF_CREATE_FLAG_NONE, nullptr);
+    if (result != S_OK) {
+        qCWarning(lcCfApi) << "Couldn't create placeholder info for" << path << ":" << _com_error(result).ErrorMessage();
+        return "Couldn't create placeholder info";
+    }
+
+    const auto parentInfo = findPlaceholderInfo(QDir::toNativeSeparators(QFileInfo(path).absolutePath()));
+    const auto state = parentInfo && parentInfo->PinState == CF_PIN_STATE_UNPINNED ? CF_PIN_STATE_UNPINNED : CF_PIN_STATE_INHERIT;
+
+    if (!setPinState(path, state, CF_SET_PIN_FLAG_NONE)) {
+        return "Couldn't set the default inherit pin state";
+    }
+
+    return {};
+}
+
+OCC::Result<void, QString> updatePlaceholderInfo(const QString &path, time_t modtime, qint64 size, const QByteArray &fileId, const QString &replacesPath = QString())
+{
+    auto info = findPlaceholderInfo(replacesPath.isEmpty() ? path : replacesPath);
+    if (!info) {
+        return "Can't update non existing placeholder info";
+    }
+
+    const auto previousPinState = info->PinState;
+
+    auto handle = handleForPath(path);
+    if (!handle) {
+        return "Can't update placeholder info for non existing file";
+    }
+
+    const auto fileIdentity = QString::fromUtf8(fileId).toStdWString();
+    const auto fileIdentitySize = (fileIdentity.length() + 1) * sizeof(wchar_t);
+
+    CF_FS_METADATA metadata;
+    metadata.FileSize.QuadPart = size;
+    OCC::Utility::UnixTimeToLargeIntegerFiletime(modtime, &metadata.BasicInfo.CreationTime);
+    OCC::Utility::UnixTimeToLargeIntegerFiletime(modtime, &metadata.BasicInfo.LastWriteTime);
+    OCC::Utility::UnixTimeToLargeIntegerFiletime(modtime, &metadata.BasicInfo.LastAccessTime);
+    OCC::Utility::UnixTimeToLargeIntegerFiletime(modtime, &metadata.BasicInfo.ChangeTime);
+
+    const qint64 result = CfUpdatePlaceholder(handle.get(), &metadata,
+                                              fileIdentity.data(), sizeToDWORD(fileIdentitySize),
+                                              nullptr, 0, CF_UPDATE_FLAG_NONE, nullptr, nullptr);
+
+    if (result != S_OK) {
+        qCWarning(lcCfApi) << "Couldn't update placeholder info for" << path << ":" << _com_error(result).ErrorMessage();
+        return "Couldn't update placeholder info";
+    }
+
+    // Pin state tends to be lost on updates, so restore it every time
+    if (!setPinState(path, previousPinState, CF_SET_PIN_FLAG_NONE)) {
+        return "Couldn't restore pin state";
+    }
+
+    return {};
+}
+
+void convertToPlaceholder(const QString &path, time_t modtime, qint64 size, const QByteArray &fileId, const QString &replacesPath)
+{
+    auto handle = handleForPath(path);
+    Q_ASSERT(handle);
+
+    const auto fileIdentity = QString::fromUtf8(fileId).toStdWString();
+    const auto fileIdentitySize = (fileIdentity.length() + 1) * sizeof(wchar_t);
+    const qint64 result = CfConvertToPlaceholder(handle.get(), fileIdentity.data(), sizeToDWORD(fileIdentitySize), CF_CONVERT_FLAG_NONE, nullptr, nullptr);
+    Q_ASSERT(result == S_OK);
+    if (result != S_OK) {
+        qCCritical(lcCfApi) << "Couldn't convert to placeholder" << path << ":" << _com_error(result).ErrorMessage();
+        return;
+    }
+
+    const auto originalInfo = findPlaceholderInfo(replacesPath);
+    if (!originalInfo) {
+        const auto stateResult = setPinState(path, CF_PIN_STATE_INHERIT, CF_SET_PIN_FLAG_NONE);
+        Q_ASSERT(stateResult);
+    } else {
+        const auto stateResult = setPinState(path, originalInfo->PinState, CF_SET_PIN_FLAG_NONE);
+        Q_ASSERT(stateResult);
+    }
+}
+
+namespace OCC {
+
+class VfsCfApiPrivate
+{
+public:
+    CF_CONNECTION_KEY callbackConnectionKey = {};
+};
+
+VfsCfApi::VfsCfApi(QObject *parent)
+    : Vfs(parent)
+    , d(new VfsCfApiPrivate)
+{
+}
+
+VfsCfApi::~VfsCfApi() = default;
+
+Vfs::Mode VfsCfApi::mode() const
+{
+    return WindowsCfApi;
+}
+
+QString VfsCfApi::fileSuffix() const
+{
+    return {};
+}
+
+void VfsCfApi::startImpl(const VfsSetupParams &params)
+{
+    const auto localPath = QDir::toNativeSeparators(params.filesystemPath);
+
+    const auto providerName = params.providerName.toStdWString();
+    const auto providerVersion = params.providerVersion.toStdWString();
+
+    CF_SYNC_REGISTRATION info;
+    info.ProviderName = providerName.data();
+    info.ProviderVersion = providerVersion.data();
+    info.SyncRootIdentity = nullptr;
+    info.SyncRootIdentityLength = 0;
+    info.FileIdentity = nullptr;
+    info.FileIdentityLength = 0;
+
+    CF_SYNC_POLICIES policies;
+    policies.Hydration.Primary = CF_HYDRATION_POLICY_FULL;
+    policies.Hydration.Modifier = CF_HYDRATION_POLICY_MODIFIER_NONE;
+    policies.Population.Primary = CF_POPULATION_POLICY_ALWAYS_FULL;
+    policies.Population.Modifier = CF_POPULATION_POLICY_MODIFIER_NONE;
+    policies.InSync = CF_INSYNC_POLICY_PRESERVE_INSYNC_FOR_SYNC_ENGINE;
+    policies.HardLink = CF_HARDLINK_POLICY_NONE;
+
+    const qint64 registerResult = CfRegisterSyncRoot(localPath.toStdWString().data(), &info, &policies, CF_REGISTER_FLAG_UPDATE);
+    Q_ASSERT(registerResult == S_OK);
+    if (registerResult != S_OK) {
+        qCCritical(lcCfApi) << "Initialization failed, couldn't register sync root:" << _com_error(registerResult).ErrorMessage();
+        return;
+    }
+
+
+    const qint64 connectResult = CfConnectSyncRoot(localPath.toStdWString().data(),
+                                                   cfApiCallbacks,
+                                                   nullptr,
+                                                   CF_CONNECT_FLAG_REQUIRE_PROCESS_INFO | CF_CONNECT_FLAG_REQUIRE_FULL_FILE_PATH,
+                                                   &d->callbackConnectionKey);
+    Q_ASSERT(connectResult == S_OK);
+    if (connectResult != S_OK) {
+        qCCritical(lcCfApi) << "Initialization failed, couldn't connect sync root:" << _com_error(connectResult).ErrorMessage();
+    }
+}
+
+void VfsCfApi::stop()
+{
+    CfDisconnectSyncRoot(d->callbackConnectionKey);
+}
+
+void VfsCfApi::unregisterFolder()
+{
+    const auto localPath = QDir::toNativeSeparators(params().filesystemPath).toStdWString();
+    CfUnregisterSyncRoot(localPath.data());
+}
+
+bool VfsCfApi::socketApiPinStateActionsShown() const
+{
+    return true;
+}
+
+bool VfsCfApi::isHydrating() const
+{
+    return false;
+}
+
+Result<void, QString> VfsCfApi::updateMetadata(const QString &filePath, time_t modtime, qint64 size, const QByteArray &fileId)
+{
+    const auto localPath = QDir::toNativeSeparators(filePath);
+    return updatePlaceholderInfo(localPath, modtime, size, fileId);
+}
+
+Result<void, QString> VfsCfApi::createPlaceholder(const SyncFileItem &item)
+{
+    Q_ASSERT(params().filesystemPath.endsWith('/'));
+    const auto localPath = QDir::toNativeSeparators(params().filesystemPath + item._file);
+    const auto result = createPlaceholderInfo(localPath, item._modtime, item._size, item._fileId);
+    return result;
+}
+
+Result<void, QString> VfsCfApi::dehydratePlaceholder(const SyncFileItem &item)
+{
+    const auto previousPin = pinState(item._file);
+
+    if (!QFile::remove(_setupParams.filesystemPath + item._file)) {
+        return QStringLiteral("Couldn't remove %1 to fulfill dehydration").arg(item._file);
+    }
+
+    const auto r = createPlaceholder(item);
+    if (!r) {
+        return r;
+    }
+
+    if (previousPin) {
+        if (*previousPin == PinState::AlwaysLocal) {
+            setPinState(item._file, PinState::Unspecified);
+        } else {
+            setPinState(item._file, *previousPin);
+        }
+    }
+
+    return {};
+}
+
+void VfsCfApi::convertToPlaceholder(const QString &filename, const SyncFileItem &item, const QString &replacesFile)
+{
+    const auto localPath = QDir::toNativeSeparators(filename);
+    const auto replacesPath = QDir::toNativeSeparators(replacesFile);
+    if (findPlaceholderInfo(localPath)) {
+        updatePlaceholderInfo(localPath, item._modtime, item._size, item._fileId, replacesPath);
+    } else {
+        ::convertToPlaceholder(localPath, item._modtime, item._size, item._fileId, replacesPath);
+    }
+}
+
+bool VfsCfApi::needsMetadataUpdate(const SyncFileItem &item)
+{
+    return false;
+}
+
+bool VfsCfApi::isDehydratedPlaceholder(const QString &filePath)
+{
+    const auto path = QDir::toNativeSeparators(filePath).toStdWString();
+    const auto attributes = GetFileAttributes(path.data());
+    return (attributes & FILE_ATTRIBUTE_SPARSE_FILE) != 0;
+}
+
+bool VfsCfApi::statTypeVirtualFile(csync_file_stat_t *stat, void *statData)
+{
+    const auto ffd = static_cast<WIN32_FIND_DATA *>(statData);
+
+    const auto isDirectory = (ffd->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0;
+    const auto isSparseFile = (ffd->dwFileAttributes & FILE_ATTRIBUTE_SPARSE_FILE) != 0;
+    const auto isPinned = (ffd->dwFileAttributes & FILE_ATTRIBUTE_PINNED) != 0;
+    const auto isUnpinned = (ffd->dwFileAttributes & FILE_ATTRIBUTE_UNPINNED) != 0;
+    const auto hasReparsePoint = (ffd->dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) != 0;
+    const auto hasCloudTag = (ffd->dwReserved0 & IO_REPARSE_TAG_CLOUD) != 0;
+
+    // It's a dir with a reparse point due to the placeholder info (hence the cloud tag)
+    // if we don't remove the reparse point flag the discovery will end up thinking
+    // it is a file... let's prevent it
+    if (isDirectory && hasReparsePoint && hasCloudTag) {
+        ffd->dwFileAttributes &= ~FILE_ATTRIBUTE_REPARSE_POINT;
+        return false;
+    } else if (isSparseFile && isPinned) {
+        stat->type = ItemTypeVirtualFileDownload;
+        return true;
+    } else if (!isSparseFile && isUnpinned){
+        stat->type = ItemTypeVirtualFileDehydration;
+        return true;
+    } else if (isSparseFile) {
+        stat->type = ItemTypeVirtualFile;
+        return true;
+    }
+
+    return false;
+}
+
+bool VfsCfApi::setPinState(const QString &folderPath, PinState state)
+{
+    const auto localPath = QDir::toNativeSeparators(params().filesystemPath + folderPath);
+
+    auto cfState = CF_PIN_STATE_UNSPECIFIED;
+    switch (state) {
+    case PinState::AlwaysLocal:
+        cfState = CF_PIN_STATE_PINNED;
+        break;
+    case PinState::Inherited:
+        cfState = CF_PIN_STATE_INHERIT;
+        break;
+    case PinState::OnlineOnly:
+        cfState = CF_PIN_STATE_UNPINNED;
+        break;
+    case PinState::Unspecified:
+        cfState = CF_PIN_STATE_UNSPECIFIED;
+        break;
+    default:
+        Q_UNREACHABLE();
+        return false;
+    }
+
+    return ::setPinState(localPath, cfState, CF_SET_PIN_FLAG_RECURSE);
+}
+
+Optional<PinState> VfsCfApi::pinState(const QString &folderPath)
+{
+    const auto localPath = QDir::toNativeSeparators(params().filesystemPath + folderPath);
+    const auto info = findPlaceholderInfo(localPath);
+    if (!info) {
+        return {};
+    }
+
+    switch (info->PinState) {
+    case CF_PIN_STATE_UNSPECIFIED:
+        return PinState::Unspecified;
+    case CF_PIN_STATE_PINNED:
+        return PinState::AlwaysLocal;
+    case CF_PIN_STATE_UNPINNED:
+        return PinState::OnlineOnly;
+    case CF_PIN_STATE_INHERIT:
+        return PinState::Inherited;
+    default:
+        Q_UNREACHABLE();
+        return {};
+    }
+}
+
+Vfs::AvailabilityResult VfsCfApi::availability(const QString &folderPath)
+{
+    const auto basePinState = pinState(folderPath);
+    const auto hydrationAndPinStates = computeRecursiveHydrationAndPinStates(folderPath, basePinState);
+
+    const auto pin = hydrationAndPinStates.pinState;
+    const auto hydrationStatus = hydrationAndPinStates.hydrationStatus;
+
+    if (hydrationStatus.hasDehydrated) {
+        if (hydrationStatus.hasHydrated)
+            return VfsItemAvailability::Mixed;
+        if (pin && *pin == PinState::OnlineOnly)
+            return VfsItemAvailability::OnlineOnly;
+        else
+            return VfsItemAvailability::AllDehydrated;
+    } else if (hydrationStatus.hasHydrated) {
+        if (pin && *pin == PinState::AlwaysLocal)
+            return VfsItemAvailability::AlwaysLocal;
+        else
+            return VfsItemAvailability::AllHydrated;
+    }
+    return AvailabilityError::NoSuchItem;
+}
+
+void VfsCfApi::fileStatusChanged(const QString &systemFileName, SyncFileStatus fileStatus)
+{
+    Q_UNUSED(systemFileName);
+    Q_UNUSED(fileStatus);
+}
+
+VfsCfApi::HydratationAndPinStates VfsCfApi::computeRecursiveHydrationAndPinStates(const QString &folderPath, const Optional<PinState> &basePinState)
+{
+    Q_ASSERT(!folderPath.endsWith('/'));
+    QFileInfo info(params().filesystemPath + folderPath);
+
+    if (!info.exists()) {
+        return {};
+    }
+
+    const auto effectivePin = pinState(folderPath);
+    const auto pinResult = (!effectivePin && !basePinState) ? Optional<PinState>()
+                         : (!effectivePin || !basePinState) ? PinState::Inherited
+                         : (*effectivePin == *basePinState) ? *effectivePin
+                         : PinState::Inherited;
+
+    if (info.isDir()) {
+        const auto dirState = HydratationAndPinStates {
+            pinResult,
+            {}
+        };
+        const auto dir = QDir(info.absoluteFilePath());
+        Q_ASSERT(dir.exists());
+        const auto children = dir.entryList();
+        return std::accumulate(std::cbegin(children), std::cend(children), dirState, [=](const HydratationAndPinStates &currentState, const QString &name) {
+            if (name == QStringLiteral("..") || name == QStringLiteral(".")) {
+                return currentState;
+            }
+
+            const auto path = folderPath + '/' + name;
+            const auto states = computeRecursiveHydrationAndPinStates(path, currentState.pinState);
+            return HydratationAndPinStates {
+                states.pinState,
+                {
+                    states.hydrationStatus.hasHydrated || currentState.hydrationStatus.hasHydrated,
+                    states.hydrationStatus.hasDehydrated || currentState.hydrationStatus.hasDehydrated,
+                }
+            };
+        });
+    } else { // file case
+        const auto isDehydrated = isDehydratedPlaceholder(info.absoluteFilePath());
+        return {
+            pinResult,
+            {
+                !isDehydrated,
+                isDehydrated
+            }
+        };
+    }
+}
+
+} // namespace OCC
+
+OCC_DEFINE_VFS_FACTORY("win", OCC::VfsCfApi)

src/libsync/vfs/cfapi/vfs_cfapi.h

@@ -0,0 +1,75 @@
+/*
+ * Copyright (C) by Kevin Ottens <kevin.ottens@nextcloud.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+#pragma once
+
+#include <QObject>
+#include <QScopedPointer>
+
+#include "common/vfs.h"
+
+namespace OCC {
+class VfsCfApiPrivate;
+
+class VfsCfApi : public Vfs
+{
+    Q_OBJECT
+
+public:
+    explicit VfsCfApi(QObject *parent = nullptr);
+    ~VfsCfApi();
+
+    Mode mode() const override;
+    QString fileSuffix() const override;
+
+    void stop() override;
+    void unregisterFolder() override;
+
+    bool socketApiPinStateActionsShown() const override;
+    bool isHydrating() const override;
+
+    Result<void, QString> updateMetadata(const QString &filePath, time_t modtime, qint64 size, const QByteArray &fileId) override;
+
+    Result<void, QString> createPlaceholder(const SyncFileItem &item) override;
+    Result<void, QString> dehydratePlaceholder(const SyncFileItem &item) override;
+    void convertToPlaceholder(const QString &filename, const SyncFileItem &item, const QString &replacesFile) override;
+
+    bool needsMetadataUpdate(const SyncFileItem &) override;
+    bool isDehydratedPlaceholder(const QString &filePath) override;
+    bool statTypeVirtualFile(csync_file_stat_t *stat, void *statData) override;
+
+    bool setPinState(const QString &folderPath, PinState state) override;
+    Optional<PinState> pinState(const QString &folderPath) override;
+    AvailabilityResult availability(const QString &folderPath) override;
+
+public slots:
+    void fileStatusChanged(const QString &systemFileName, SyncFileStatus fileStatus) override;
+
+protected:
+    void startImpl(const VfsSetupParams &params) override;
+
+private:
+    struct HasHydratedDehydrated {
+        bool hasHydrated = false;
+        bool hasDehydrated = false;
+    };
+    struct HydratationAndPinStates {
+        Optional<PinState> pinState;
+        HasHydratedDehydrated hydrationStatus;
+    };
+    HydratationAndPinStates computeRecursiveHydrationAndPinStates(const QString &path, const Optional<PinState> &basePinState);
+
+    QScopedPointer<VfsCfApiPrivate> d;
+};
+
+} // namespace OCC

test/CMakeLists.txt

@@ -73,6 +73,10 @@ if( UNIX AND NOT APPLE )
     nextcloud_add_test(InotifyWatcher "${FolderWatcher_SRC}")
 endif(UNIX AND NOT APPLE)
 
+if (WIN32)
+    nextcloud_add_test(SyncCfApi "")
+endif()
+
 nextcloud_add_benchmark(LargeSync "")
 
 SET(FolderMan_SRC ../src/gui/folderman.cpp)

test/testsynccfapi.cpp

@@ -0,0 +1,1344 @@
+/*
+ *    This software is in the public domain, furnished "as is", without technical
+ *    support, and with no warranty, express or implied, as to its usefulness for
+ *    any purpose.
+ *
+ */
+
+#include <QtTest>
+#include "syncenginetestutils.h"
+#include "common/vfs.h"
+#include "config.h"
+#include <syncengine.h>
+
+#include <cfapi.h>
+
+using namespace OCC;
+
+bool isSparseFile(const QString &path)
+{
+    auto p = path;
+    const auto attributes = GetFileAttributes(reinterpret_cast<wchar_t *>(p.data()));
+    return (attributes & FILE_ATTRIBUTE_SPARSE_FILE) != 0;
+}
+
+std::unique_ptr<void, void(*)(HANDLE)> handleForPath(const QString &path)
+{
+    if (QFileInfo(path).isDir()) {
+        HANDLE handle = nullptr;
+        const qint64 openResult = CfOpenFileWithOplock(path.toStdWString().data(), CF_OPEN_FILE_FLAG_NONE, &handle);
+        if (openResult == S_OK) {
+            return {handle, CfCloseHandle};
+        }
+    } else {
+        const auto handle = CreateFile(path.toStdWString().data(), 0, 0, nullptr,
+                                       OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, nullptr);
+        if (handle != INVALID_HANDLE_VALUE) {
+            return {handle, [](HANDLE h) { CloseHandle(h); }};
+        }
+    }
+
+    return {nullptr, [](HANDLE){}};
+}
+
+void setPinState(const QString &path, PinState state, bool recurse = false)
+{
+    auto p = QDir::toNativeSeparators(path);
+    const auto handle = handleForPath(p);
+    Q_ASSERT(handle);
+
+    auto cfState = CF_PIN_STATE_UNSPECIFIED;
+    switch (state) {
+    case PinState::AlwaysLocal:
+        cfState = CF_PIN_STATE_PINNED;
+        break;
+    case PinState::Inherited:
+        cfState = CF_PIN_STATE_INHERIT;
+        break;
+    case PinState::OnlineOnly:
+        cfState = CF_PIN_STATE_UNPINNED;
+        break;
+    case PinState::Unspecified:
+        cfState = CF_PIN_STATE_UNSPECIFIED;
+        break;
+    }
+
+    if (recurse) {
+        const qint64 result = CfSetPinState(handle.get(), cfState, CF_SET_PIN_FLAG_RECURSE, nullptr);
+        Q_ASSERT(result == S_OK);
+    } else {
+        const qint64 result = CfSetPinState(handle.get(), cfState, CF_SET_PIN_FLAG_NONE, nullptr);
+        Q_ASSERT(result == S_OK);
+
+        const qint64 childrenResult = CfSetPinState(handle.get(), CF_PIN_STATE_INHERIT, CF_SET_PIN_FLAG_RECURSE_ONLY, nullptr);
+        Q_ASSERT(childrenResult == S_OK);
+    }
+}
+
+bool itemInstruction(const ItemCompletedSpy &spy, const QString &path, const SyncInstructions instr)
+{
+    auto item = spy.findItem(path);
+    return item->_instruction == instr;
+}
+
+SyncJournalFileRecord dbRecord(FakeFolder &folder, const QString &path)
+{
+    SyncJournalFileRecord record;
+    folder.syncJournal().getFileRecord(path, &record);
+    return record;
+}
+
+void triggerDownload(FakeFolder &folder, const QByteArray &path)
+{
+    auto &journal = folder.syncJournal();
+    SyncJournalFileRecord record;
+    journal.getFileRecord(path, &record);
+    if (!record.isValid())
+        return;
+    record._type = ItemTypeVirtualFileDownload;
+    journal.setFileRecord(record);
+    journal.schedulePathForRemoteDiscovery(record._path);
+}
+
+void markForDehydration(FakeFolder &folder, const QByteArray &path)
+{
+    auto &journal = folder.syncJournal();
+    SyncJournalFileRecord record;
+    journal.getFileRecord(path, &record);
+    if (!record.isValid())
+        return;
+    record._type = ItemTypeVirtualFileDehydration;
+    journal.setFileRecord(record);
+    journal.schedulePathForRemoteDiscovery(record._path);
+}
+
+QSharedPointer<Vfs> setupVfs(FakeFolder &folder)
+{
+    auto cfapiVfs = QSharedPointer<Vfs>(createVfsFromPlugin(Vfs::WindowsCfApi).release());
+    QObject::connect(&folder.syncEngine().syncFileStatusTracker(), &SyncFileStatusTracker::fileStatusChanged,
+                     cfapiVfs.data(), &Vfs::fileStatusChanged);
+    folder.switchToVfs(cfapiVfs);
+
+    setPinState(folder.localPath(), PinState::Unspecified);
+
+    return cfapiVfs;
+}
+
+class TestSyncCfApi : public QObject
+{
+    Q_OBJECT
+
+private slots:
+    void testVirtualFileLifecycle_data()
+    {
+        QTest::addColumn<bool>("doLocalDiscovery");
+
+        QTest::newRow("full local discovery") << true;
+        QTest::newRow("skip local discovery") << false;
+    }
+
+    void testVirtualFileLifecycle()
+    {
+        QFETCH(bool, doLocalDiscovery);
+
+        FakeFolder fakeFolder{ FileInfo() };
+        setupVfs(fakeFolder);
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+        ItemCompletedSpy completeSpy(fakeFolder);
+
+        auto cleanup = [&]() {
+            completeSpy.clear();
+            if (!doLocalDiscovery)
+                fakeFolder.syncEngine().setLocalDiscoveryOptions(LocalDiscoveryStyle::DatabaseAndFilesystem);
+        };
+        cleanup();
+
+        // Create a virtual file for a new remote file
+        fakeFolder.remoteModifier().mkdir("A");
+        fakeFolder.remoteModifier().insert("A/a1", 64);
+        auto someDate = QDateTime(QDate(1984, 07, 30), QTime(1,3,2));
+        fakeFolder.remoteModifier().setModTime("A/a1", someDate);
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a1").size(), 64);
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a1").lastModified(), someDate);
+        QVERIFY(fakeFolder.currentRemoteState().find("A/a1"));
+        QVERIFY(itemInstruction(completeSpy, "A/a1", CSYNC_INSTRUCTION_NEW));
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeVirtualFile);
+        cleanup();
+
+        // Another sync doesn't actually lead to changes
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a1").size(), 64);
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a1").lastModified(), someDate);
+        QVERIFY(fakeFolder.currentRemoteState().find("A/a1"));
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeVirtualFile);
+        QVERIFY(completeSpy.isEmpty());
+        cleanup();
+
+        // Not even when the remote is rediscovered
+        fakeFolder.syncJournal().forceRemoteDiscoveryNextSync();
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a1").size(), 64);
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a1").lastModified(), someDate);
+        QVERIFY(fakeFolder.currentRemoteState().find("A/a1"));
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeVirtualFile);
+        QVERIFY(completeSpy.isEmpty());
+        cleanup();
+
+        // Neither does a remote change
+        fakeFolder.remoteModifier().appendByte("A/a1");
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a1").size(), 65);
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a1").lastModified(), someDate);
+        QVERIFY(fakeFolder.currentRemoteState().find("A/a1"));
+        QVERIFY(itemInstruction(completeSpy, "A/a1", CSYNC_INSTRUCTION_UPDATE_METADATA));
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._fileSize, 65);
+        cleanup();
+
+        // If the local virtual file is removed, this will be propagated remotely
+        if (!doLocalDiscovery)
+            fakeFolder.syncEngine().setLocalDiscoveryOptions(LocalDiscoveryStyle::DatabaseAndFilesystem, { "A" });
+        fakeFolder.localModifier().remove("A/a1");
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(!fakeFolder.currentLocalState().find("A/a1"));
+        QVERIFY(!fakeFolder.currentRemoteState().find("A/a1"));
+        QVERIFY(itemInstruction(completeSpy, "A/a1", CSYNC_INSTRUCTION_REMOVE));
+        QVERIFY(!dbRecord(fakeFolder, "A/a1").isValid());
+        cleanup();
+
+        // Recreate a1 before carrying on with the other tests
+        fakeFolder.remoteModifier().insert("A/a1", 65);
+        fakeFolder.remoteModifier().setModTime("A/a1", someDate);
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a1").size(), 65);
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a1").lastModified(), someDate);
+        QVERIFY(fakeFolder.currentRemoteState().find("A/a1"));
+        QVERIFY(itemInstruction(completeSpy, "A/a1", CSYNC_INSTRUCTION_NEW));
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeVirtualFile);
+        cleanup();
+
+        // Remote rename is propagated
+        fakeFolder.remoteModifier().rename("A/a1", "A/a1m");
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "A/a1").exists());
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a1m"));
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a1m").size(), 65);
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a1m").lastModified(), someDate);
+        QVERIFY(!fakeFolder.currentRemoteState().find("A/a1"));
+        QVERIFY(fakeFolder.currentRemoteState().find("A/a1m"));
+        QVERIFY(
+            itemInstruction(completeSpy, "A/a1m", CSYNC_INSTRUCTION_RENAME)
+            || (itemInstruction(completeSpy, "A/a1m", CSYNC_INSTRUCTION_NEW)
+                && itemInstruction(completeSpy, "A/a1", CSYNC_INSTRUCTION_REMOVE)));
+        QVERIFY(!dbRecord(fakeFolder, "A/a1").isValid());
+        QCOMPARE(dbRecord(fakeFolder, "A/a1m")._type, ItemTypeVirtualFile);
+        cleanup();
+
+        // Remote remove is propagated
+        fakeFolder.remoteModifier().remove("A/a1m");
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "A/a1m").exists());
+        QVERIFY(!fakeFolder.currentRemoteState().find("A/a1m"));
+        QVERIFY(itemInstruction(completeSpy, "A/a1m", CSYNC_INSTRUCTION_REMOVE));
+        QVERIFY(!dbRecord(fakeFolder, "A/a1").isValid());
+        QVERIFY(!dbRecord(fakeFolder, "A/a1m").isValid());
+        cleanup();
+
+        // Edge case: Local virtual file but no db entry for some reason
+        fakeFolder.remoteModifier().insert("A/a2", 32);
+        fakeFolder.remoteModifier().insert("A/a3", 33);
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a2"));
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a2").size(), 32);
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a3"));
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a3").size(), 33);
+        cleanup();
+
+        fakeFolder.syncEngine().journal()->deleteFileRecord("A/a2");
+        fakeFolder.syncEngine().journal()->deleteFileRecord("A/a3");
+        fakeFolder.remoteModifier().remove("A/a3");
+        fakeFolder.syncEngine().setLocalDiscoveryOptions(LocalDiscoveryStyle::FilesystemOnly);
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a2"));
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a2").size(), 32);
+        QVERIFY(itemInstruction(completeSpy, "A/a2", CSYNC_INSTRUCTION_UPDATE_METADATA));
+        QVERIFY(dbRecord(fakeFolder, "A/a2").isValid());
+        QCOMPARE(dbRecord(fakeFolder, "A/a2")._type, ItemTypeVirtualFile);
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "A/a3").exists());
+        QVERIFY(itemInstruction(completeSpy, "A/a3", CSYNC_INSTRUCTION_REMOVE));
+        QVERIFY(!dbRecord(fakeFolder, "A/a3").isValid());
+        cleanup();
+    }
+
+    void testVirtualFileConflict()
+    {
+        FakeFolder fakeFolder{ FileInfo() };
+        setupVfs(fakeFolder);
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+        ItemCompletedSpy completeSpy(fakeFolder);
+
+        auto cleanup = [&]() {
+            completeSpy.clear();
+        };
+        cleanup();
+
+        // Create a virtual file for a new remote file
+        fakeFolder.remoteModifier().mkdir("A");
+        fakeFolder.remoteModifier().insert("A/a1", 11);
+        fakeFolder.remoteModifier().insert("A/a2", 12);
+        fakeFolder.remoteModifier().mkdir("B");
+        fakeFolder.remoteModifier().insert("B/b1", 21);
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a2"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "B/b1"));
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a1").size(), 11);
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/a2").size(), 12);
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "B/b1").size(), 21);
+        cleanup();
+
+        // All the files are touched on the server
+        fakeFolder.remoteModifier().appendByte("A/a1");
+        fakeFolder.remoteModifier().appendByte("A/a2");
+        fakeFolder.remoteModifier().appendByte("B/b1");
+
+        // A: the correct file and a conflicting file are added
+        // B: user adds a *directory* locally
+        fakeFolder.localModifier().remove("A/a1");
+        fakeFolder.localModifier().insert("A/a1", 12);
+        fakeFolder.localModifier().remove("A/a2");
+        fakeFolder.localModifier().insert("A/a2", 10);
+        fakeFolder.localModifier().remove("B/b1");
+        fakeFolder.localModifier().mkdir("B/b1");
+        fakeFolder.localModifier().insert("B/b1/foo");
+        QVERIFY(fakeFolder.syncOnce());
+
+        // Everything is CONFLICT
+        QVERIFY(itemInstruction(completeSpy, "A/a1", CSYNC_INSTRUCTION_CONFLICT));
+        QVERIFY(itemInstruction(completeSpy, "A/a2", CSYNC_INSTRUCTION_CONFLICT));
+        QVERIFY(itemInstruction(completeSpy, "B/b1", CSYNC_INSTRUCTION_CONFLICT));
+
+        // conflict files should exist
+        QCOMPARE(fakeFolder.syncJournal().conflictRecordPaths().size(), 2);
+
+        // nothing should have the virtual file tag
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/a2"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "B/b1"));
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a2")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "B/b1")._type, ItemTypeFile);
+
+        cleanup();
+    }
+
+    void testWithNormalSync()
+    {
+        FakeFolder fakeFolder{ FileInfo::A12_B12_C12_S12() };
+        setupVfs(fakeFolder);
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+        ItemCompletedSpy completeSpy(fakeFolder);
+
+        auto cleanup = [&]() {
+            completeSpy.clear();
+        };
+        cleanup();
+
+        // No effect sync
+        QVERIFY(fakeFolder.syncOnce());
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+        cleanup();
+
+        // Existing files are propagated just fine in both directions
+        fakeFolder.localModifier().appendByte("A/a1");
+        fakeFolder.localModifier().insert("A/a3");
+        fakeFolder.remoteModifier().appendByte("A/a2");
+        QVERIFY(fakeFolder.syncOnce());
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+        cleanup();
+
+        // New files on the remote create virtual files
+        fakeFolder.remoteModifier().insert("A/new", 42);
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/new"));
+        QCOMPARE(QFileInfo(fakeFolder.localPath() + "A/new").size(), 42);
+        QVERIFY(fakeFolder.currentRemoteState().find("A/new"));
+        QVERIFY(itemInstruction(completeSpy, "A/new", CSYNC_INSTRUCTION_NEW));
+        QCOMPARE(dbRecord(fakeFolder, "A/new")._type, ItemTypeVirtualFile);
+        cleanup();
+    }
+
+    void testVirtualFileDownload()
+    {
+        FakeFolder fakeFolder{ FileInfo() };
+        setupVfs(fakeFolder);
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+        ItemCompletedSpy completeSpy(fakeFolder);
+
+        auto cleanup = [&]() {
+            completeSpy.clear();
+        };
+        cleanup();
+
+        // Create a virtual file for remote files
+        fakeFolder.remoteModifier().mkdir("A");
+        fakeFolder.remoteModifier().insert("A/a1");
+        fakeFolder.remoteModifier().insert("A/a2");
+        fakeFolder.remoteModifier().insert("A/a3");
+        fakeFolder.remoteModifier().insert("A/a4");
+        fakeFolder.remoteModifier().insert("A/a5");
+        fakeFolder.remoteModifier().insert("A/a6");
+        fakeFolder.remoteModifier().insert("A/a7");
+        fakeFolder.remoteModifier().insert("A/b1");
+        fakeFolder.remoteModifier().insert("A/b2");
+        fakeFolder.remoteModifier().insert("A/b3");
+        fakeFolder.remoteModifier().insert("A/b4");
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a2"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a3"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a4"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a5"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a6"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a7"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/b1"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/b2"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/b3"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/b4"));
+
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a2").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a3").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a4").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a5").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a6").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a7").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/b1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/b2").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/b3").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/b4").exists());
+
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a2")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a3")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a4")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a5")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a6")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a7")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/b1")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/b2")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/b3")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/b4")._type, ItemTypeVirtualFile);
+
+        cleanup();
+
+        // Download by changing the db entry
+        triggerDownload(fakeFolder, "A/a1");
+        triggerDownload(fakeFolder, "A/a2");
+        triggerDownload(fakeFolder, "A/a3");
+        triggerDownload(fakeFolder, "A/a4");
+        triggerDownload(fakeFolder, "A/a5");
+        triggerDownload(fakeFolder, "A/a6");
+        triggerDownload(fakeFolder, "A/a7");
+        triggerDownload(fakeFolder, "A/b1");
+        triggerDownload(fakeFolder, "A/b2");
+        triggerDownload(fakeFolder, "A/b3");
+        triggerDownload(fakeFolder, "A/b4");
+
+        // Remote complications
+        fakeFolder.remoteModifier().appendByte("A/a2");
+        fakeFolder.remoteModifier().remove("A/a3");
+        fakeFolder.remoteModifier().rename("A/a4", "A/a4m");
+        fakeFolder.remoteModifier().appendByte("A/b2");
+        fakeFolder.remoteModifier().remove("A/b3");
+        fakeFolder.remoteModifier().rename("A/b4", "A/b4m");
+
+        // Local complications
+        fakeFolder.localModifier().remove("A/a5");
+        fakeFolder.localModifier().insert("A/a5");
+        fakeFolder.localModifier().remove("A/a6");
+        fakeFolder.localModifier().insert("A/a6");
+
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(itemInstruction(completeSpy, "A/a1", CSYNC_INSTRUCTION_SYNC));
+        QCOMPARE(completeSpy.findItem("A/a1")->_type, ItemTypeVirtualFileDownload);
+        QVERIFY(itemInstruction(completeSpy, "A/a2", CSYNC_INSTRUCTION_SYNC));
+        QCOMPARE(completeSpy.findItem("A/a2")->_type, ItemTypeVirtualFileDownload);
+        QVERIFY(itemInstruction(completeSpy, "A/a3", CSYNC_INSTRUCTION_REMOVE));
+        QVERIFY(itemInstruction(completeSpy, "A/a4m", CSYNC_INSTRUCTION_NEW));
+        QVERIFY(itemInstruction(completeSpy, "A/a4", CSYNC_INSTRUCTION_REMOVE));
+        QVERIFY(itemInstruction(completeSpy, "A/a5", CSYNC_INSTRUCTION_CONFLICT));
+        QVERIFY(itemInstruction(completeSpy, "A/a6", CSYNC_INSTRUCTION_CONFLICT));
+        QVERIFY(itemInstruction(completeSpy, "A/a7", CSYNC_INSTRUCTION_SYNC));
+        QVERIFY(itemInstruction(completeSpy, "A/b1", CSYNC_INSTRUCTION_SYNC));
+        QVERIFY(itemInstruction(completeSpy, "A/b2", CSYNC_INSTRUCTION_SYNC));
+        QVERIFY(itemInstruction(completeSpy, "A/b3", CSYNC_INSTRUCTION_REMOVE));
+        QVERIFY(itemInstruction(completeSpy, "A/b4m", CSYNC_INSTRUCTION_NEW));
+        QVERIFY(itemInstruction(completeSpy, "A/b4", CSYNC_INSTRUCTION_REMOVE));
+
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/a2"));
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "A/a3").exists());
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "A/a4").exists());
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/a4m"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/a5"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/a6"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/a7"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/b1"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/b2"));
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "A/b3").exists());
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "A/b4").exists());
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/b4m"));
+
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a2")._type, ItemTypeFile);
+        QVERIFY(!dbRecord(fakeFolder, "A/a3").isValid());
+        QCOMPARE(dbRecord(fakeFolder, "A/a4m")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a5")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a6")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a7")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/b1")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/b2")._type, ItemTypeFile);
+        QVERIFY(!dbRecord(fakeFolder, "A/b3").isValid());
+        QCOMPARE(dbRecord(fakeFolder, "A/b4m")._type, ItemTypeFile);
+
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+    }
+
+    void testVirtualFileDownloadResume()
+    {
+        FakeFolder fakeFolder{ FileInfo() };
+        setupVfs(fakeFolder);
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+        ItemCompletedSpy completeSpy(fakeFolder);
+
+        auto cleanup = [&]() {
+            completeSpy.clear();
+            fakeFolder.syncJournal().wipeErrorBlacklist();
+        };
+        cleanup();
+
+        // Create a virtual file for remote files
+        fakeFolder.remoteModifier().mkdir("A");
+        fakeFolder.remoteModifier().insert("A/a1");
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a1").exists());
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeVirtualFile);
+        cleanup();
+
+        // Download by changing the db entry
+        triggerDownload(fakeFolder, "A/a1");
+        fakeFolder.serverErrorPaths().append("A/a1", 500);
+        QVERIFY(!fakeFolder.syncOnce());
+        QVERIFY(itemInstruction(completeSpy, "A/a1", CSYNC_INSTRUCTION_SYNC));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a1").exists());
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeVirtualFileDownload);
+        cleanup();
+
+        fakeFolder.serverErrorPaths().clear();
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(itemInstruction(completeSpy, "A/a1", CSYNC_INSTRUCTION_SYNC));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeFile);
+    }
+
+    void testNewFilesNotVirtual()
+    {
+        FakeFolder fakeFolder{ FileInfo() };
+        setupVfs(fakeFolder);
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+
+        fakeFolder.remoteModifier().mkdir("A");
+        fakeFolder.remoteModifier().insert("A/a1");
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a1").exists());
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeVirtualFile);
+
+        setPinState(fakeFolder.localPath(), PinState::AlwaysLocal);
+
+        // Create a new remote file, it'll not be virtual
+        fakeFolder.remoteModifier().insert("A/a2");
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/a2"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a2").exists());
+        QCOMPARE(dbRecord(fakeFolder, "A/a2")._type, ItemTypeFile);
+    }
+
+    void testDownloadRecursive()
+    {
+        FakeFolder fakeFolder{ FileInfo() };
+        setupVfs(fakeFolder);
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+
+        // Create a virtual file for remote files
+        fakeFolder.remoteModifier().mkdir("A");
+        fakeFolder.remoteModifier().mkdir("A/Sub");
+        fakeFolder.remoteModifier().mkdir("A/Sub/SubSub");
+        fakeFolder.remoteModifier().mkdir("A/Sub2");
+        fakeFolder.remoteModifier().mkdir("B");
+        fakeFolder.remoteModifier().mkdir("B/Sub");
+        fakeFolder.remoteModifier().insert("A/a1");
+        fakeFolder.remoteModifier().insert("A/a2");
+        fakeFolder.remoteModifier().insert("A/Sub/a3");
+        fakeFolder.remoteModifier().insert("A/Sub/a4");
+        fakeFolder.remoteModifier().insert("A/Sub/SubSub/a5");
+        fakeFolder.remoteModifier().insert("A/Sub2/a6");
+        fakeFolder.remoteModifier().insert("B/b1");
+        fakeFolder.remoteModifier().insert("B/Sub/b2");
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a2"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/Sub/a3"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/Sub/a4"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/Sub/SubSub/a5"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/Sub2/a6"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "B/b1"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "B/Sub/b2"));
+
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a2").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/Sub/a3").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/Sub/a4").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/Sub/SubSub/a5").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/Sub2/a6").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "B/b1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "B/Sub/b2").exists());
+
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a2")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/Sub/a3")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/Sub/a4")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/Sub/SubSub/a5")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/Sub2/a6")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "B/b1")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "B/Sub/b2")._type, ItemTypeVirtualFile);
+
+        // Download All file in the directory A/Sub
+        // (as in Folder::downloadVirtualFile)
+        fakeFolder.syncJournal().markVirtualFileForDownloadRecursively("A/Sub");
+
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a2"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/Sub/a3"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/Sub/a4"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/Sub/SubSub/a5"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/Sub2/a6"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "B/b1"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "B/Sub/b2"));
+
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a2").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/Sub/a3").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/Sub/a4").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/Sub/SubSub/a5").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/Sub2/a6").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "B/b1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "B/Sub/b2").exists());
+
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a2")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/Sub/a3")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/Sub/a4")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/Sub/SubSub/a5")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/Sub2/a6")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "B/b1")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "B/Sub/b2")._type, ItemTypeVirtualFile);
+
+        // Add a file in a subfolder that was downloaded
+        // Currently, this continue to add it as a virtual file.
+        fakeFolder.remoteModifier().insert("A/Sub/SubSub/a7");
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/Sub/SubSub/a7"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/Sub/SubSub/a7").exists());
+        QCOMPARE(dbRecord(fakeFolder, "A/Sub/SubSub/a7")._type, ItemTypeVirtualFile);
+
+        // Now download all files in "A"
+        fakeFolder.syncJournal().markVirtualFileForDownloadRecursively("A");
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/a2"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/Sub/a3"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/Sub/a4"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/Sub/SubSub/a5"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/Sub/SubSub/a7"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "A/Sub2/a6"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "B/b1"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "B/Sub/b2"));
+
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a2").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/Sub/a3").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/Sub/a4").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/Sub/SubSub/a5").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/Sub/SubSub/a7").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/Sub2/a6").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "B/b1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "B/Sub/b2").exists());
+
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a2")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/Sub/a3")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/Sub/a4")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/Sub/SubSub/a5")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/Sub/SubSub/a7")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/Sub2/a6")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "B/b1")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "B/Sub/b2")._type, ItemTypeVirtualFile);
+
+        // Now download remaining files in "B"
+        fakeFolder.syncJournal().markVirtualFileForDownloadRecursively("B");
+        QVERIFY(fakeFolder.syncOnce());
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+    }
+
+    void testRenameVirtual()
+    {
+        FakeFolder fakeFolder{ FileInfo() };
+        setupVfs(fakeFolder);
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+        ItemCompletedSpy completeSpy(fakeFolder);
+
+        auto cleanup = [&]() {
+            completeSpy.clear();
+        };
+        cleanup();
+
+        fakeFolder.remoteModifier().insert("file1", 128, 'C');
+        fakeFolder.remoteModifier().insert("file2", 256, 'C');
+        fakeFolder.remoteModifier().insert("file3", 256, 'C');
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "file1"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "file2"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "file3"));
+
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "file1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "file2").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "file3").exists());
+
+        QCOMPARE(dbRecord(fakeFolder, "file1")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "file2")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "file3")._type, ItemTypeVirtualFile);
+
+        cleanup();
+
+        fakeFolder.localModifier().rename("file1", "renamed1");
+        fakeFolder.localModifier().rename("file2", "renamed2");
+        triggerDownload(fakeFolder, "file2");
+        triggerDownload(fakeFolder, "file3");
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "file1").exists());
+        QVERIFY(!dbRecord(fakeFolder, "file1").isValid());
+
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "renamed1"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "renamed1").exists());
+        QCOMPARE(dbRecord(fakeFolder, "renamed1")._type, ItemTypeVirtualFile);
+
+        QVERIFY(fakeFolder.currentRemoteState().find("renamed1"));
+        QVERIFY(itemInstruction(completeSpy, "renamed1", CSYNC_INSTRUCTION_RENAME));
+
+        // file2 has a conflict between the download request and the rename:
+        // the rename wins, the download is ignored
+
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "file2").exists());
+        QVERIFY(!dbRecord(fakeFolder, "file2").isValid());
+
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "renamed2"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "renamed2").exists());
+        QCOMPARE(dbRecord(fakeFolder, "renamed2")._type, ItemTypeVirtualFile);
+
+        QVERIFY(fakeFolder.currentRemoteState().find("renamed2"));
+        QVERIFY(itemInstruction(completeSpy, "renamed2", CSYNC_INSTRUCTION_RENAME));
+
+        QVERIFY(itemInstruction(completeSpy, "file3", CSYNC_INSTRUCTION_SYNC));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "file3"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "file3").exists());
+        QVERIFY(dbRecord(fakeFolder, "file3")._type == ItemTypeFile);
+        cleanup();
+    }
+
+    void testRenameVirtual2()
+    {
+        FakeFolder fakeFolder{ FileInfo() };
+        setupVfs(fakeFolder);
+        ItemCompletedSpy completeSpy(fakeFolder);
+        auto cleanup = [&]() {
+            completeSpy.clear();
+        };
+        cleanup();
+
+        fakeFolder.remoteModifier().insert("case3", 128, 'C');
+        fakeFolder.remoteModifier().insert("case4", 256, 'C');
+        QVERIFY(fakeFolder.syncOnce());
+
+        triggerDownload(fakeFolder, "case4");
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "case3"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "case4"));
+
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "case3").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "case4").exists());
+
+        QCOMPARE(dbRecord(fakeFolder, "case3")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "case4")._type, ItemTypeFile);
+
+        cleanup();
+
+        // Case 1: non-virtual, foo -> bar (tested elsewhere)
+        // Case 2: virtual, foo -> bar (tested elsewhere)
+
+        // Case 3: virtual, foo.oc -> bar.oc (db hydrate)
+        fakeFolder.localModifier().rename("case3", "case3-rename");
+        triggerDownload(fakeFolder, "case3");
+
+        // Case 4: non-virtual foo -> bar (db dehydrate)
+        fakeFolder.localModifier().rename("case4", "case4-rename");
+        markForDehydration(fakeFolder, "case4");
+
+        QVERIFY(fakeFolder.syncOnce());
+
+        // Case 3: the rename went though, hydration is forgotten
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "case3").exists());
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "case3-rename"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "case3-rename").exists());
+        QVERIFY(!fakeFolder.currentRemoteState().find("case3"));
+        QVERIFY(fakeFolder.currentRemoteState().find("case3-rename"));
+        QVERIFY(itemInstruction(completeSpy, "case3-rename", CSYNC_INSTRUCTION_RENAME));
+        QVERIFY(dbRecord(fakeFolder, "case3-rename")._type == ItemTypeVirtualFile);
+
+        // Case 4: the rename went though, dehydration is forgotten
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "case4").exists());
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "case4-rename"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "case4-rename").exists());
+        QVERIFY(!fakeFolder.currentRemoteState().find("case4"));
+        QVERIFY(fakeFolder.currentRemoteState().find("case4-rename"));
+        QVERIFY(itemInstruction(completeSpy, "case4-rename", CSYNC_INSTRUCTION_RENAME));
+        QVERIFY(dbRecord(fakeFolder, "case4-rename")._type == ItemTypeFile);
+    }
+
+    // Dehydration via sync works
+    void testSyncDehydration()
+    {
+        FakeFolder fakeFolder{ FileInfo::A12_B12_C12_S12() };
+        setupVfs(fakeFolder);
+
+        QVERIFY(fakeFolder.syncOnce());
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+
+        ItemCompletedSpy completeSpy(fakeFolder);
+        auto cleanup = [&]() {
+            completeSpy.clear();
+        };
+        cleanup();
+
+        //
+        // Mark for dehydration and check
+        //
+
+        markForDehydration(fakeFolder, "A/a1");
+
+        markForDehydration(fakeFolder, "A/a2");
+        fakeFolder.remoteModifier().appendByte("A/a2");
+        // expect: normal dehydration
+
+        markForDehydration(fakeFolder, "B/b1");
+        fakeFolder.remoteModifier().remove("B/b1");
+        // expect: local removal
+
+        markForDehydration(fakeFolder, "B/b2");
+        fakeFolder.remoteModifier().rename("B/b2", "B/b3");
+        // expect: B/b2 is gone, B/b3 is NEW placeholder
+
+        markForDehydration(fakeFolder, "C/c1");
+        fakeFolder.localModifier().appendByte("C/c1");
+        // expect: no dehydration, upload of c1
+
+        markForDehydration(fakeFolder, "C/c2");
+        fakeFolder.localModifier().appendByte("C/c2");
+        fakeFolder.remoteModifier().appendByte("C/c2");
+        fakeFolder.remoteModifier().appendByte("C/c2");
+        // expect: no dehydration, conflict
+
+        QVERIFY(fakeFolder.syncOnce());
+
+        auto isDehydrated = [&](const QString &path) {
+            return isSparseFile(fakeFolder.localPath() + path)
+                && QFileInfo(fakeFolder.localPath() + path).exists();
+        };
+        auto hasDehydratedDbEntries = [&](const QString &path) {
+            SyncJournalFileRecord rec;
+            fakeFolder.syncJournal().getFileRecord(path, &rec);
+            return rec.isValid() && rec._type == ItemTypeVirtualFile;
+        };
+
+        QVERIFY(isDehydrated("A/a1"));
+        QVERIFY(hasDehydratedDbEntries("A/a1"));
+        QVERIFY(itemInstruction(completeSpy, "A/a1", CSYNC_INSTRUCTION_SYNC));
+        QCOMPARE(completeSpy.findItem("A/a1")->_type, ItemTypeVirtualFileDehydration);
+        QCOMPARE(completeSpy.findItem("A/a1")->_file, QStringLiteral("A/a1"));
+        QVERIFY(isDehydrated("A/a2"));
+        QVERIFY(hasDehydratedDbEntries("A/a2"));
+        QVERIFY(itemInstruction(completeSpy, "A/a2", CSYNC_INSTRUCTION_SYNC));
+        QCOMPARE(completeSpy.findItem("A/a2")->_type, ItemTypeVirtualFileDehydration);
+
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "B/b1").exists());
+        QVERIFY(!fakeFolder.currentRemoteState().find("B/b1"));
+        QVERIFY(itemInstruction(completeSpy, "B/b1", CSYNC_INSTRUCTION_REMOVE));
+
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "B/b2").exists());
+        QVERIFY(!fakeFolder.currentRemoteState().find("B/b2"));
+        QVERIFY(isDehydrated("B/b3"));
+        QVERIFY(hasDehydratedDbEntries("B/b3"));
+        QVERIFY(itemInstruction(completeSpy, "B/b2", CSYNC_INSTRUCTION_REMOVE));
+        QVERIFY(itemInstruction(completeSpy, "B/b3", CSYNC_INSTRUCTION_NEW));
+
+        QCOMPARE(fakeFolder.currentRemoteState().find("C/c1")->size, 25);
+        QVERIFY(itemInstruction(completeSpy, "C/c1", CSYNC_INSTRUCTION_SYNC));
+
+        QCOMPARE(fakeFolder.currentRemoteState().find("C/c2")->size, 26);
+        QVERIFY(itemInstruction(completeSpy, "C/c2", CSYNC_INSTRUCTION_CONFLICT));
+        cleanup();
+
+        auto expectedRemoteState = fakeFolder.currentRemoteState();
+        QVERIFY(fakeFolder.syncOnce());
+        QCOMPARE(fakeFolder.currentRemoteState(), expectedRemoteState);
+
+        QVERIFY(isDehydrated("A/a1"));
+        QVERIFY(hasDehydratedDbEntries("A/a1"));
+        QVERIFY(isDehydrated("A/a2"));
+        QVERIFY(hasDehydratedDbEntries("A/a2"));
+
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "B/b1").exists());
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "B/b2").exists());
+        QVERIFY(isDehydrated("B/b3"));
+        QVERIFY(hasDehydratedDbEntries("B/b3"));
+
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "C/c1").exists());
+        QVERIFY(dbRecord(fakeFolder, "C/c1").isValid());
+        QVERIFY(!isDehydrated("C/c1"));
+        QVERIFY(!hasDehydratedDbEntries("C/c1"));
+
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "C/c2").exists());
+        QVERIFY(dbRecord(fakeFolder, "C/c2").isValid());
+        QVERIFY(!isDehydrated("C/c2"));
+        QVERIFY(!hasDehydratedDbEntries("C/c2"));
+    }
+
+    void testWipeVirtualSuffixFiles()
+    {
+        FakeFolder fakeFolder{ FileInfo{} };
+        setupVfs(fakeFolder);
+
+        // Create a suffix-vfs baseline
+
+        fakeFolder.remoteModifier().mkdir("A");
+        fakeFolder.remoteModifier().mkdir("A/B");
+        fakeFolder.remoteModifier().insert("f1");
+        fakeFolder.remoteModifier().insert("A/a1");
+        fakeFolder.remoteModifier().insert("A/a3");
+        fakeFolder.remoteModifier().insert("A/B/b1");
+        fakeFolder.localModifier().mkdir("A");
+        fakeFolder.localModifier().mkdir("A/B");
+        fakeFolder.localModifier().insert("f2");
+        fakeFolder.localModifier().insert("A/a2");
+        fakeFolder.localModifier().insert("A/B/b2");
+
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "f1"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a1"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/a3"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "A/B/b1"));
+
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "f1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a3").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/B/b1").exists());
+
+        QCOMPARE(dbRecord(fakeFolder, "f1")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a1")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/a3")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "A/B/b1")._type, ItemTypeVirtualFile);
+
+        // Make local changes to a3
+        fakeFolder.localModifier().remove("A/a3");
+        fakeFolder.localModifier().insert("A/a3", 100);
+
+        // Now wipe the virtuals
+        SyncEngine::wipeVirtualFiles(fakeFolder.localPath(), fakeFolder.syncJournal(), *fakeFolder.syncEngine().syncOptions()._vfs);
+
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "f1").exists());
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "A/a1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "A/a3").exists());
+        QVERIFY(!QFileInfo(fakeFolder.localPath() + "A/B/b1").exists());
+
+        QVERIFY(!dbRecord(fakeFolder, "f1").isValid());
+        QVERIFY(!dbRecord(fakeFolder, "A/a1").isValid());
+        QVERIFY(!dbRecord(fakeFolder, "A/a3").isValid());
+        QVERIFY(!dbRecord(fakeFolder, "A/B/b1").isValid());
+
+        fakeFolder.switchToVfs(QSharedPointer<Vfs>(new VfsOff));
+        ItemCompletedSpy completeSpy(fakeFolder);
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(fakeFolder.currentLocalState().find("A"));
+        QVERIFY(fakeFolder.currentLocalState().find("A/B"));
+        QVERIFY(fakeFolder.currentLocalState().find("A/B/b1"));
+        QVERIFY(fakeFolder.currentLocalState().find("A/B/b2"));
+        QVERIFY(fakeFolder.currentLocalState().find("A/a1"));
+        QVERIFY(fakeFolder.currentLocalState().find("A/a2"));
+        QVERIFY(fakeFolder.currentLocalState().find("A/a3"));
+        QVERIFY(fakeFolder.currentLocalState().find("f1"));
+        QVERIFY(fakeFolder.currentLocalState().find("f2"));
+
+        // a3 has a conflict
+        QVERIFY(itemInstruction(completeSpy, "A/a3", CSYNC_INSTRUCTION_CONFLICT));
+
+        // conflict files should exist
+        QCOMPARE(fakeFolder.syncJournal().conflictRecordPaths().size(), 1);
+    }
+
+    void testNewVirtuals()
+    {
+        FakeFolder fakeFolder{ FileInfo() };
+        setupVfs(fakeFolder);
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+
+        fakeFolder.remoteModifier().mkdir("local");
+        fakeFolder.remoteModifier().mkdir("online");
+        fakeFolder.remoteModifier().mkdir("unspec");
+        QVERIFY(fakeFolder.syncOnce());
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+
+        setPinState(fakeFolder.localPath() + "local", PinState::AlwaysLocal, true);
+        setPinState(fakeFolder.localPath() + "online", PinState::OnlineOnly, true);
+        setPinState(fakeFolder.localPath() + "unspec", PinState::Unspecified, true);
+
+        // Test 1: root is Unspecified
+        fakeFolder.remoteModifier().insert("file1");
+        fakeFolder.remoteModifier().insert("online/file1");
+        fakeFolder.remoteModifier().insert("local/file1");
+        fakeFolder.remoteModifier().insert("unspec/file1");
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "file1"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "online/file1"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "local/file1"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "unspec/file1"));
+
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "file1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "online/file1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "local/file1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "unspec/file1").exists());
+
+        QCOMPARE(dbRecord(fakeFolder, "file1")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "online/file1")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "local/file1")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "unspec/file1")._type, ItemTypeVirtualFile);
+
+        // Test 2: change root to AlwaysLocal
+        setPinState(fakeFolder.localPath(), PinState::AlwaysLocal, true);
+        // Need to force pin state for the subfolders again
+        setPinState(fakeFolder.localPath() + "local", PinState::AlwaysLocal, true);
+        setPinState(fakeFolder.localPath() + "online", PinState::OnlineOnly, true);
+        setPinState(fakeFolder.localPath() + "unspec", PinState::Unspecified, true);
+
+        fakeFolder.remoteModifier().insert("file2");
+        fakeFolder.remoteModifier().insert("online/file2");
+        fakeFolder.remoteModifier().insert("local/file2");
+        fakeFolder.remoteModifier().insert("unspec/file2");
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "file2"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "online/file2"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "local/file2"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "unspec/file2"));
+
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "file2").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "online/file2").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "local/file2").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "unspec/file2").exists());
+
+        QCOMPARE(dbRecord(fakeFolder, "file2")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "online/file2")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "local/file2")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "unspec/file2")._type, ItemTypeVirtualFile);
+
+        // root file1 was hydrated due to its new pin state
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "file1"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "file1").exists());
+        QCOMPARE(dbRecord(fakeFolder, "file1")._type, ItemTypeFile);
+
+        // file1 is unchanged in the explicitly pinned subfolders
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "online/file1"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "local/file1"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "unspec/file1"));
+
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "online/file1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "local/file1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "unspec/file1").exists());
+
+        QCOMPARE(dbRecord(fakeFolder, "online/file1")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "local/file1")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "unspec/file1")._type, ItemTypeVirtualFile);
+
+        // Test 3: change root to OnlineOnly
+        setPinState(fakeFolder.localPath(), PinState::OnlineOnly, true);
+        // Need to force pin state for the subfolders again
+        setPinState(fakeFolder.localPath() + "local", PinState::AlwaysLocal, true);
+        setPinState(fakeFolder.localPath() + "online", PinState::OnlineOnly, true);
+        setPinState(fakeFolder.localPath() + "unspec", PinState::Unspecified, true);
+
+        fakeFolder.remoteModifier().insert("file3");
+        fakeFolder.remoteModifier().insert("online/file3");
+        fakeFolder.remoteModifier().insert("local/file3");
+        fakeFolder.remoteModifier().insert("unspec/file3");
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "file3"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "online/file3"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "local/file3"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "unspec/file3"));
+
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "file3").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "online/file3").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "local/file3").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "unspec/file3").exists());
+
+        QCOMPARE(dbRecord(fakeFolder, "file3")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "online/file3")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "local/file3")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "unspec/file3")._type, ItemTypeVirtualFile);
+
+
+        // root file1 was dehydrated due to its new pin state
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "file1"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "file1").exists());
+        QCOMPARE(dbRecord(fakeFolder, "file1")._type, ItemTypeVirtualFile);
+
+        // file1 is unchanged in the explicitly pinned subfolders
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "online/file1"));
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "local/file1"));
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "unspec/file1"));
+
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "online/file1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "local/file1").exists());
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "unspec/file1").exists());
+
+        QCOMPARE(dbRecord(fakeFolder, "online/file1")._type, ItemTypeVirtualFile);
+        QCOMPARE(dbRecord(fakeFolder, "local/file1")._type, ItemTypeFile);
+        QCOMPARE(dbRecord(fakeFolder, "unspec/file1")._type, ItemTypeVirtualFile);
+    }
+
+    void testAvailability()
+    {
+        FakeFolder fakeFolder{ FileInfo() };
+        auto vfs = setupVfs(fakeFolder);
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+
+        fakeFolder.remoteModifier().mkdir("local");
+        fakeFolder.remoteModifier().mkdir("local/sub");
+        fakeFolder.remoteModifier().mkdir("online");
+        fakeFolder.remoteModifier().mkdir("online/sub");
+        fakeFolder.remoteModifier().mkdir("unspec");
+        QVERIFY(fakeFolder.syncOnce());
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+
+        setPinState(fakeFolder.localPath() + "local", PinState::AlwaysLocal, true);
+        setPinState(fakeFolder.localPath() + "online", PinState::OnlineOnly, true);
+        setPinState(fakeFolder.localPath() + "unspec", PinState::Unspecified, true);
+
+        fakeFolder.remoteModifier().insert("file1");
+        fakeFolder.remoteModifier().insert("online/file1");
+        fakeFolder.remoteModifier().insert("online/file2");
+        fakeFolder.remoteModifier().insert("local/file1");
+        fakeFolder.remoteModifier().insert("local/file2");
+        fakeFolder.remoteModifier().insert("unspec/file1");
+        QVERIFY(fakeFolder.syncOnce());
+
+        // root is unspecified
+        QCOMPARE(*vfs->availability("file1"), VfsItemAvailability::AllDehydrated);
+        QCOMPARE(*vfs->availability("local"), VfsItemAvailability::AlwaysLocal);
+        QCOMPARE(*vfs->availability("local/file1"), VfsItemAvailability::AlwaysLocal);
+        QCOMPARE(*vfs->availability("online"), VfsItemAvailability::OnlineOnly);
+        QCOMPARE(*vfs->availability("online/file1"), VfsItemAvailability::OnlineOnly);
+        QCOMPARE(*vfs->availability("unspec"), VfsItemAvailability::AllDehydrated);
+        QCOMPARE(*vfs->availability("unspec/file1"), VfsItemAvailability::AllDehydrated);
+
+        // Subitem pin states can ruin "pure" availabilities
+        setPinState(fakeFolder.localPath() + "local/sub", PinState::OnlineOnly);
+        QCOMPARE(*vfs->availability("local"), VfsItemAvailability::AllHydrated);
+        setPinState(fakeFolder.localPath() + "online/sub", PinState::Unspecified);
+        QCOMPARE(*vfs->availability("online"), VfsItemAvailability::AllDehydrated);
+
+        triggerDownload(fakeFolder, "unspec/file1");
+        setPinState(fakeFolder.localPath() + "local/file2", PinState::OnlineOnly);
+        setPinState(fakeFolder.localPath() + "online/file2", PinState::AlwaysLocal);
+        QVERIFY(fakeFolder.syncOnce());
+
+        QCOMPARE(*vfs->availability("unspec"), VfsItemAvailability::AllHydrated);
+        QCOMPARE(*vfs->availability("local"), VfsItemAvailability::Mixed);
+        QCOMPARE(*vfs->availability("online"), VfsItemAvailability::Mixed);
+
+        vfs->setPinState("local", PinState::AlwaysLocal);
+        vfs->setPinState("online", PinState::OnlineOnly);
+        QVERIFY(fakeFolder.syncOnce());
+
+        QCOMPARE(*vfs->availability("online"), VfsItemAvailability::OnlineOnly);
+        QCOMPARE(*vfs->availability("local"), VfsItemAvailability::AlwaysLocal);
+
+        auto r = vfs->availability("nonexistant");
+        QVERIFY(!r);
+        QCOMPARE(r.error(), Vfs::AvailabilityError::NoSuchItem);
+    }
+
+    void testPinStateLocals()
+    {
+        FakeFolder fakeFolder{ FileInfo() };
+        auto vfs = setupVfs(fakeFolder);
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+
+        fakeFolder.remoteModifier().mkdir("local");
+        fakeFolder.remoteModifier().mkdir("online");
+        fakeFolder.remoteModifier().mkdir("unspec");
+        QVERIFY(fakeFolder.syncOnce());
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+
+        setPinState(fakeFolder.localPath() + "local", PinState::AlwaysLocal);
+        setPinState(fakeFolder.localPath() + "online", PinState::OnlineOnly);
+        setPinState(fakeFolder.localPath() + "unspec", PinState::Unspecified);
+
+        fakeFolder.localModifier().insert("file1");
+        fakeFolder.localModifier().insert("online/file1");
+        fakeFolder.localModifier().insert("online/file2");
+        fakeFolder.localModifier().insert("local/file1");
+        fakeFolder.localModifier().insert("unspec/file1");
+        QVERIFY(fakeFolder.syncOnce());
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+
+        // root is unspecified
+        QCOMPARE(*vfs->pinState("file1"), PinState::Unspecified);
+        QCOMPARE(*vfs->pinState("local/file1"), PinState::AlwaysLocal);
+        QCOMPARE(*vfs->pinState("online/file1"), PinState::Unspecified);
+        QCOMPARE(*vfs->pinState("unspec/file1"), PinState::Unspecified);
+
+        // Sync again: bad pin states of new local files usually take effect on second sync
+        QVERIFY(fakeFolder.syncOnce());
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+
+        // When a file in an online-only folder is renamed, it retains its pin
+        fakeFolder.localModifier().rename("online/file1", "online/file1rename");
+        fakeFolder.remoteModifier().rename("online/file2", "online/file2rename");
+        QVERIFY(fakeFolder.syncOnce());
+        QCOMPARE(*vfs->pinState("online/file1rename"), PinState::Unspecified);
+        QCOMPARE(*vfs->pinState("online/file2rename"), PinState::Unspecified);
+
+        // When a folder is renamed, the pin states inside should be retained
+        fakeFolder.localModifier().rename("online", "onlinerenamed1");
+        QVERIFY(fakeFolder.syncOnce());
+        QCOMPARE(*vfs->pinState("onlinerenamed1"), PinState::OnlineOnly);
+        QCOMPARE(*vfs->pinState("onlinerenamed1/file1rename"), PinState::Unspecified);
+
+        fakeFolder.remoteModifier().rename("onlinerenamed1", "onlinerenamed2");
+        QVERIFY(fakeFolder.syncOnce());
+        QCOMPARE(*vfs->pinState("onlinerenamed2"), PinState::OnlineOnly);
+        QCOMPARE(*vfs->pinState("onlinerenamed2/file1rename"), PinState::Unspecified);
+
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+
+        // When a file is deleted and later a new file has the same name, the old pin
+        // state isn't preserved.
+        QCOMPARE(*vfs->pinState("onlinerenamed2/file1rename"), PinState::Unspecified);
+        fakeFolder.remoteModifier().remove("onlinerenamed2/file1rename");
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(!vfs->pinState("onlinerenamed2/file1rename"));
+        fakeFolder.remoteModifier().insert("onlinerenamed2/file1rename");
+        QVERIFY(fakeFolder.syncOnce());
+        QCOMPARE(*vfs->pinState("onlinerenamed2/file1rename"), PinState::OnlineOnly);
+
+        // When a file is hydrated or dehydrated due to pin state it retains its pin state
+        vfs->setPinState("onlinerenamed2/file1rename", PinState::AlwaysLocal);
+        QVERIFY(fakeFolder.syncOnce());
+        QVERIFY(fakeFolder.currentLocalState().find("onlinerenamed2/file1rename"));
+        QCOMPARE(*vfs->pinState("onlinerenamed2/file1rename"), PinState::AlwaysLocal);
+
+        vfs->setPinState("onlinerenamed2", PinState::Unspecified);
+        vfs->setPinState("onlinerenamed2/file1rename", PinState::OnlineOnly);
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "onlinerenamed2/file1rename"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "onlinerenamed2/file1rename").exists());
+        QCOMPARE(dbRecord(fakeFolder, "onlinerenamed2/file1rename")._type, ItemTypeVirtualFile);
+
+        QCOMPARE(*vfs->pinState("onlinerenamed2/file1rename"), PinState::OnlineOnly);
+    }
+
+    void testIncompatiblePins()
+    {
+        FakeFolder fakeFolder{ FileInfo() };
+        auto vfs = setupVfs(fakeFolder);
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+
+        fakeFolder.remoteModifier().mkdir("local");
+        fakeFolder.remoteModifier().mkdir("online");
+        QVERIFY(fakeFolder.syncOnce());
+        QCOMPARE(fakeFolder.currentLocalState(), fakeFolder.currentRemoteState());
+
+        setPinState(fakeFolder.localPath() + "local", PinState::AlwaysLocal);
+        setPinState(fakeFolder.localPath() + "online", PinState::OnlineOnly);
+
+        fakeFolder.localModifier().insert("local/file1");
+        fakeFolder.localModifier().insert("online/file1");
+        QVERIFY(fakeFolder.syncOnce());
+
+        markForDehydration(fakeFolder, "local/file1");
+        triggerDownload(fakeFolder, "online/file1");
+
+        // the sync sets the changed files pin states to unspecified
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "online/file1"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "online/file1").exists());
+        QCOMPARE(dbRecord(fakeFolder, "online/file1")._type, ItemTypeFile);
+
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "local/file1"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "local/file1").exists());
+        QCOMPARE(dbRecord(fakeFolder, "local/file1")._type, ItemTypeVirtualFile);
+
+        QCOMPARE(*vfs->pinState("online/file1"), PinState::Unspecified);
+        QCOMPARE(*vfs->pinState("local/file1"), PinState::Unspecified);
+
+        // no change on another sync
+        QVERIFY(fakeFolder.syncOnce());
+
+        QVERIFY(!isSparseFile(fakeFolder.localPath() + "online/file1"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "online/file1").exists());
+        QCOMPARE(dbRecord(fakeFolder, "online/file1")._type, ItemTypeFile);
+
+        QVERIFY(isSparseFile(fakeFolder.localPath() + "local/file1"));
+        QVERIFY(QFileInfo(fakeFolder.localPath() + "local/file1").exists());
+        QCOMPARE(dbRecord(fakeFolder, "local/file1")._type, ItemTypeVirtualFile);
+    }
+};
+
+QTEST_GUILESS_MAIN(TestSyncCfApi)
+#include "testsynccfapi.moc"